1. Field of the Invention
The invention relates to a handle for a hand tool, especially a screwdriver grip, as used for example for various screwing jobs.
2. Discussion of the Prior Art
It is known to use screwdriver grips on the one end face of which different tool inserts or tool shanks with various active parts, for example supporting screwdrivers, cross-slotted screwdrivers, a hexagon/hexagon socket, can be exchangeably fastened, for example by means of a clamping sleeve. These handles cannot be used in conjunction with tool kits known per se, in particular ratchet screwdriver kits, which contain various button dies and bits. Moreover, in each case they can be used only in their classic form as screwdrivers, that is to say for screwing jobs in which relatively little force has to be exerted, while for greater torques it is necessary to resort to a T grip, or in situations were space is restricted, to a revolver grip. Consequently, three different tools have to be respectively provided for three different working situations.
German reference DE 36 36 025 C2 does indeed disclose a screwdriver grip in which a tool accessory, such as a hexagon-socket wrench, can be fastened on the grip part in two different settings, to be precise in a longitudinally axial position and a central position perpendicular to the latter, whereby a T grip is obtained. For these different types of arrangement, the tool insert has a head part, which can be push-inserted into a corresponding slot of the grip in different positions. Apart from the fact that, with this known grip, only a normal screwdriver function and a T-screwdriver function can be achieved, it also cannot be used for further commercially available tool inserts, since only tool inserts with the special head designed for this grip can be used.
The object of the invention is to provide a handle of the type mentioned above which is capable of being used in three different screwing/working positions, that is to say as a screwdriver, a T grip and a revolver grip, in rapid combination, with commercially available tools or inserts, button dies, bits, ratchets etc. and which, moreover, has a structure which is as simple as possible.
Accordingly, the handle according to the invention has, as provisions for fastening the various tool inserts on its handle body, at least two polygonal locating shanks, onto which the known tool inserts can be attached by being fitted on via their locating sleeves. In this case, a first shank is arranged on one end face of the tool body coaxially in longitudinal alignment so as to protrude, while at least one further shank, aligned at an angle and at a distance from the first shank, is provided. This provides a simple way of creating a multiple or multi-grip which, in combination with accessories offered inexpensively on the market, represents a multi-functional screwdriver quickly and easily, without special clamping provisions or special configurations.
It is particularly advantageous if three locating shanks are provided on the handle body, there being arranged in addition to the first shank, protruding in a longitudinally axial manner, a second shank perpendicular to the longitudinal axis and consequently in relation to the first shank and at the same time central to the longitudinal extent of the handle. As a result, the handle can be used as a T grip. Moreover, a third shank is arranged in the zone of the end face of the handle opposite the first shank, to be precise at an angle of 90 to 120xc2x0 in relation to the alignment of the first shank or to the longitudinal axis of the handle, whereby a revolver grip can be provided. Particularly advantageous in this case is the 120xc2x0 position, in which the shank terminates essentially at the end-face edge, obtaining a sloping revolver grip with a particularly good action.
The multi-grip according to the invention, which can consequently be used as a simple screwdriver, as a T grip and as a revolver grip, can be used as required for different torques on account of the different insert possibilities. It is also additionally possible to use a ratchet element, for example a freewheel ratchet button die according to DE 297 23 472 U1, directly or via a small adaptor plug-in part, it then being possible for the tool inserts to be fitted as required onto this ratchet. Consequently, the handle can be used in all three positions of use as a ratchet grip, in conjunction with a wide range of tool inserts. The handle can consequently be put together with. corresponding accessories to form a set, for example in a corresponding tool kit, which may include not only the screwdriver grip but also at least one ratchet element, various extensions, button dies, bits etc.
It is of advantage if the shanks in each case have a polygonal profile known per se, such as a square or hexagon profile, which interact with the corresponding inner square or inner hexagon profiles of the locating sleeves of the tool inserts or corresponding extensions or adaptor parts. It goes without saying that, in the case of an arrangement of square locating shanks in a corresponding tool set, at least one square/hexagon adaptor part is provided in order to allow tool inserts with different locating sleeves to be optimally used with the same handle.
In this case, the shanks may be arranged such that they are recessed into or protrude from the handle body to a greater or lesser extent. Therefore, they may protrude completely from the outer surface of the handle, in which case the respectively exposed length of the shank should be only slightly greater than the depth of the profile locating portion of the sleeve of the tool inserts.
The shanks may, however, also be recessed entirely or partially in the handle, in which case a coaxial, cylindrical recess is respectively provided around the shanks in the body for introducing the tool-locating sleeves. In this case, it is particularly advantageous and favorable during handling if all three shanks are recessed entirely in the handle, or at least the two shanks opening or protruding into the outer circumferential surface of the handle for the T and revolver positions. This has the effect that, in particular when the handle is being used as a classic screwdriver grip, the hand will not catch on the projecting shanks when the grip is being turned about its axis, so that injuries are avoided. The axial shank may in this case also be readily arranged in such a way that it partially or entirely protrudes from the surface, since this shank does not interfere any further with the handling of the handle.
According to the invention, the handle may be configured altogether in one piece, that is to say the shanks are arranged in or on the handle body and are, for example, cast onto the handle body during its production or worked from it subsequently.
The handle body may, however, also be produced from plastic, hard rubber, cast aluminum or other material which can be shaped, injection-molded, cast or sintered, the shanks being produced from steel or casting material and embedded in the material of the handle in a twist-resistant manner.
It is of advantage if the shanks produced from commercially available polygonal profiles, such as square or hexagon profiles, are embedded in the handle body in the form of polygonal inserts having at least two shanks and/or as individual polygonal inserts.
In this case, three individual shank inserts may be provided, in each case having a polygonal shank end and an anchorage end, with the anchorage end having a form which has been hammered out wide and flat or cut open and pressed out in an axially dovetail shape. The flat wide end or the spread-out dovetail end has the effect that a good twist- and shift-resistant anchorage of this shank takes place in the body material.
However, a single, one-part shank insert may also be provided, with three shanks, the steel profile configuration being such that two shanks are in each case provided on a correspondingly bent, commercially available profiled bar, while the third shank is provided on a second profiled bar, which is fastened on the first, bent profiled bar by adhesive bonding, welding or the like.
It is advisable here if the long part, i.e. the profiled bar bearing the axial shank and the 90xc2x0 or 120xc2x0 shank located at the opposite end, is a continuous profiled bar bent only at the 120xc2x0 part, while the central T shank is a short bar which is welded onto the long bar. In this case, a transverse groove may be made in the long profiled bar at the level of the T shank, the inner end of the short profiled bar engaging in said groove with a form fit and a welded connection being realized by spot welding from the rear side. Therefore, there is also optimal twist resistance.
However, a shorter profiled bar, bent at both ends, may also be provided, having the T shank and the revolver shank, while the axially pointing screwdriver shank is a single insert. Consequently, the shanks subjected to the greater torque loading, that is to say the T shank and the revolver shank, are anchored in the body in an optimum way in terms of loading, while the single insert subjected to less loading is provided in the screwdriver position, which has to take up less torque.
For securely locating the tool inserts, arresting devices, such as spring-loaded balls or bolts, are respectively let radially into the handle shanks, in a way known per se, and interact with corresponding recesses in the tool insert sleeves.
Finally, there is the possibility of designing the handle body in terms of material in such a way that, in particular in the case of an arrangement of single shank inserts, a material reinforcement is provided in the corresponding insertion zones, in order to achieve a greater strength in these zones, avoiding breaking out of the single shank inserts under high loading.